Digital lighting technologies, i.e. illumination based on semiconductor light sources, such as light-emitting diodes (LEDs), offer a viable alternative to traditional fluorescent, HID, and incandescent lamps. Functional advantages and benefits of LEDs include high energy conversion and optical efficiency, durability, lower operating costs, and many others. Recent advances in LED technology have provided efficient and robust full-spectrum lighting sources that enable a variety of lighting effects in many applications. Some of the fixtures embodying these sources feature a lighting module, including one or more LEDs capable of producing different colors, e.g. red, green, and blue, as well as a processor for independently controlling the output of the LEDs in order to generate a variety of colors and color-changing lighting effects.
In lighting units, such as those that include LED-based light sources, it is desirable to have control over one or more light sources of the lighting unit. For example, it may be desirable to control which of one or more light sources are illuminated and/or to control one or more lighting parameters of one or more of the light sources. For example, it may be desirable to control color, color temperature, intensity, beam width, and/or beam direction of light output provided by one or more LED-based light sources of an LED-based lighting unit.
Direct specification during configuration of a lighting unit enables control of lighting parameters. However, direct specification may suffer from one or more drawbacks such as lack of ability to fine-tune applied lighting.
A lighting control interface, such as a dimmer, may enable adjustment of one or more lighting parameters of a lighting unit that is in communication with the lighting control interface. However, many lighting control interfaces may suffer from one or more drawbacks. For example, a lighting control interface may be located a significant distance away from a lighting unit and it may not be clear to a user that the lighting control interface controls the desired lighting unit and/or it may not be convenient for a user to interact with the lighting control interface. Also, for example, a lighting control interface may control multiple lighting units and may be unable to adjust one or more lighting parameters of a single lighting unit independently of adjusting lighting parameters of other lighting units. Also, for example, a lighting control interface may be located near a lighting unit that it controls, but it may be unpleasant for a user to interact with the lighting control interface due to high levels of light output from the lighting unit.
Thus, there is a need in the art to provide methods and apparatus that enable control of one or more properties of light output of a lighting unit and that optionally overcome one or more drawbacks of existing approaches.